In general, software patches are either cumulative or non-cumulative. In the former case, a software patch (“patch”) includes previous patches released for a software product. In the latter case, the patches are independent fixes and do not include any previously released patches.
There may be different business reasons why one cannot always use cumulative patches. The reasons may include an amount of development, testing, and validation time involved to test the cumulative patches.
Non-cumulative patches may be referred to herein as Engineering Special (ES) patches, or just “ES's.” Often, engineering special patches that are built on a given release have one or more files or components in common with other engineering special patches for the same release. If there is a need for installing more than one ES on a given system, one ES might overwrite the changes done by another ES. Therefore, there is a risk that multiple ES's may not be compatible with each other. It often becomes a challenge to determine in what order the ES's should be installed in order to avoid a risk of overwriting changes by one ES with another ES. It may also become a challenge to determine which ES's need to be tested for compatibility.